Fix some issues with extension messaging:

webkit/glue/webview_impl.cc

Index: webkit/glue/webview_impl.cc
diff --git a/webkit/glue/webview_impl.cc b/webkit/glue/webview_impl.cc
index e40d27bd6f574827d7c5691bb37caa58ddbe6cec..926512973699056c8efef3c4f3b44dff384ae511 100644
--- a/webkit/glue/webview_impl.cc
+++ b/webkit/glue/webview_impl.cc
@@ -907,10 +907,6 @@ bool WebViewImpl::ShouldClose() {
 }
 
 void WebViewImpl::Close() {
-  // Do this first to prevent reentrant notifications from being sent to the
-  // initiator of the close.
-  delegate_ = NULL;
-
   if (page_.get()) {
     // Initiate shutdown for the entire frameset.  This will cause a lot of
     // notifications to be sent.
@@ -923,6 +919,10 @@ void WebViewImpl::Close() {
   if (devtools_agent_.get())
     devtools_agent_.reset(NULL);
 
+  // Do this first to prevent reentrant notifications from being sent to the
+  // initiator of the close.
+  delegate_ = NULL;
+
   Release();  // Balances AddRef from WebView::Create
 }